Crystal Palace 0 Everton 1: 'Romelu Lukaku is a joy to work with,' says Roberto Martinez

It was a scrappy goal settling a scrappy game, but when a striker needs goals, and his team needs wins, artistic merit is irrelevant.

In investing a club record £28m on Romelu Lukaku in the summer Everton used up all last season’s profit. To date the outlay has not been justified. Saturdays match-winner at Selhurst Park was Lukaku’s tenth of the season, from his 31st match. Respectable, but that fee – which Everton were persuade to pay after he scored 16 in 33 on loan last season - brings expectation.

It is fair argument that Everton have not played to Lukaku’s strengths for much of this season, and it is true that at 21 he is still learning the game. But no one thinks Jose Mourinho was wrong to let him go and spend the fee (plus £4m) on Diego Costa.

That may change as Lukaku develops. His current manager certainly has faith in him. “I think Romelu is a joy to work with,” said Roberto Martinez. “When he came back from the World Cup I don't think he was physically capable of being himself but he never shied away from the responsibility. He wanted to be there, to put himself in the spotlight. And I don't think he gets the credit he deserves.

“I think he has been very consistent with his play. He has been getting stronger and better in every game, this is the first time I would say in the last few weeks he has reached the level where he plays his best.

“He is a young man and once people see what he can do consistently they will get excited. We are all part of a team though. And if the team doesn't get the results that you want then its normal that you don't get the credit you deserve.”

Lukaku, in truth, was lucky to score at all. He knew little about his goal, scored when Julian Speroni turned Stephen Naismith’s cross into his path a few feet from goal. He previous goal, at West Ham in the FA Cup last month, was fortuitous too. But the key aspect is that on both occasions he was in the right place to benefit. Confidence may be fragile but he was still seeking to affect the game.

The goal should improve Lukaku’s confidence just as victory ought to bolster Everton’s self-belief, which is timely with the Merseyside derby this weekend. Martinez said his team could now ‘enjoy’ their football again. There was a nervousness about their early play, as Palace pressed for an equaliser, and only glimpses of the fluency of last season.

Passing teams tend to suffer most when confidence dips, as hesitancy affects their one-touch, two-touch interplay and Everton have often looked laboured this stuttering season. Their defensive solidity is, though, returning and with Mo Besic and Gareth Barry providing a shield Phil Jagielka and John Stones kept at bay a Palace side that, for the first time under Alan Pardew, looked as if they need the return from international duty of Mile Jedinak and Yannick Bolaisie.

“If we'd scored a little bit later it would have been more of a stylish performance,” said Martinez, “but today it was about scoring then managing the game and we did that.”